Heat pipe interfaces

ABSTRACT

An interface for interconnecting heat pipes is disclosed. The interface is itself a special purpose heat pipe adapted to efficiently transfer heat from the condenser of a first heat pipe to the evaporator of a second heat pipe. Using the present invention, simple heat pipes can be interconnected to form a complex heat pipe structure for particular applications.

United States Patent 1191 1111 3,831,664 Pogson Aug. 27, 1974 [5 HEAT PHE INTERFACES 1,798,951 3/1931 Munters 62/333 1 1 Invent John w Seattle, Wash- 313221323 i233? ii i s.fill...1.............IIIII"i5/f6 [73] Assignee: The Boeing Company, Seattle,

Wash. Primary Examiner-Albert W. Davis, Jr. Filed: Nov. 1973 Attorney, Agent, or Fzrm-Donaldl A. Streck 21 Appl. No.: 413,717 57 ABSTRACT An interface for interconnecting heat pipes is dis- [52] U.S. Cl 165/80, 165/105, 62/333 CIOSBd- The nte face is itself a special purpose heat [51] I111. Cl. F28d 15/00 P p adapted to fi' y r sfer heat from the con- [58] Field 01 Search 165/105, 76, 80; 62/333, denser of a first heat P p to the evaporator of a ond heat pipe. Using the present invention, simple [56] R f e Cit d heat pipes can be interconnected to form a complex UNITED STATES PATENTS heat pipe structure for particular applications. 1,753,314 4/1930 Gay 165/105 x 6 Claims, 7-Drawing Figures EVA P064 70/? ADI/18 4 77C CONDENSER PATENIEU 1x00271974 EVA P064 70/? AD/ABA T/C CONDENSER 1 HEAT PIPE INTERFACES BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to heat particularly heat pipes.

2. Description of the Prior Art A heat pipe is a closed environment containing a fluid which constantly undergoes an evaporative/condensation cycIe..A continuous wick transfers the condensed fluid from the cold portion or condenser to the hot portion or evaporator where the fluid returns to the vapor state. The vapor then moves through the closed environment in that portion of the heat pipe not occupied by the wick back to the condenser where it returns to the fluid state. If the heat pipe is to remain operative, the integrity of the cycle must be maintained. Loss of fluid continuity in the wick is the critical item in the cycle. It is particularly important when the application requires fluid flow against the force of gravity. A large complex Christmas Tree type heat pipe would be difficult and expensive to manufacture. It would be prone to operational failures from discontinuities in the wick and would have to be totally discarded if any portion became damaged or discarded. Conventional interconnecting of multiple heatpipes on the other hand would provide a cheaper, more easily fabricated structure wherein individual elements could be replaced, but, heat transfer losses at the interfaces would reduce the effectiveness of the total structure perhaps even below the level of usefulness.

Therefore, it is the prime object of the present invention to provide a cost effective apparatus for interconnecting simple multiple heat pipes into a thermally efficient complex heat pipe structure.

DESCRIPTION OF THE DRAWINGS FIG. 1 depicts a typical interface heat pipe for joining two cylindrical heat pipes.

FIG. 2 is an exploded view of one plate of an interface heat pipe for use in interconnecting a cylindrical heat pipe.

FIG. 3 depicts an interface heat pipe as shown in FIG. I interconnecting two heat pipes.

FIG. 4 depicts an interface heat pipe interconnecting three heat pipes.

FIG. 5 depicts an interface heat pipe interconnecting five heat pipes.

FIG. 6 depicts an interface heat pipe interconnecting two heat pipes wherein the junction will rotate about a single axis.

FIG. 7 depicts an interface heat pipe interconnecting two heat pipes wherein the junction forms a ball and socket joint between the two heat pipes with attendant freedom of movement.

DESCRIPTION AND OPERATION OF THE INVENTION The basis of the present invention is best understood by reference to FIG. I and FIG. 2. In FIG. I, the interface assembly It) is constructed as a heat pipe comprising an evaporator section 12, an adiabatic section 14, and a condenser section 16. The interface assembly 10 is comprised of a first plate assembly 18 and a second plate assembly 20. The first plate assembly 18 and the pipes, and more to apparatus for interconnecting multiple second plate assembly are so shaped that when positioned adjacent to one another to form the interface assembly 10 as shown in FIG. 1 they form an evaporator cavity 22 and a condenser cavity 24. FIG. 2 is an exploded view corresponding to the first plate assembly 18 of the condenser section 16 and adiabatic section 14 of FIG. 1. The first plate assembly 18 and the second plate assembly 20 of FIG. 1 are as shown in FIG. 2, comprising an outer plate 26, an outer wick 28, an inner plate 30, an inner wick 32, and spacers 34. When suitably bonded together to form an enclosure and an appropriate fluid (not shown) is inserted in the enclosure, the first plate assembly 18 and second plate assembly 20 of FIG. 1 are slab heat pipes.

FIG. 3 shows the interface assembly 10 of FIG. 1 in its preferred embodiment joining two cylindrical heat pipes. As shown in FIG. 3, the first plate assembly 40 and the second plate assembly 42 contain assembly holes 44. Bolts 46 and nuts (not shown) are fastened through the assembly holes 44 to hold first plate assembly 40 and second plate assembly 42 close against a first heat pipe 48 and a second heat pipe 50 contained within cavities 52 and 54.

Assuming the first heat pipe 48 were drawing heat from a source (not shown), the operation of the interface would be as follows. Cavity 52 would contain the condenser portion of the first heat pipe 48. Heat would flow from the evaporator portion of first heat pipe 48 (not shown) into the condenser portion. Cavity 52 would be contained in the evaporator portion of the interface heat pipe assembly 56. The condenser portion of the firstheat pipe 48 would act as a heat source for the evaporator portion of the interface heat pipe assembly 56. Heat would flow from the condenser portion of first heat pipe 48 into the evaporator portion of the interface heat pipe assembly 56 and thence into the condenser portion of the interface heat pipe assembly 56 containing cavity 54. The condenser portion of the interface heat pipe assembly 56 would act as a heat source to the evaporator portion of the second heat pipe 50 contained in cavity 54. Heat would flow into the evaporator portion of second heat pipe 50 and thence into the condenser portion of second heat pipe 50 (not shown).

FIG. 4 depicts an interface assembly 60 embodying the principles previously described into a three heat pipe interface. Typically, such an interface could be used to extract heat from two distinct sources into one cold junction. Incoming heat pipes 62 would transmit heat into evaporator cavities 64, thence to condenser cavity 66, into the evaporator portion of outgoing heat pipe 68, and thence to the cold junction (not shown).

FIG. 5 illustrates yet another evolution of the same design principle employing a five heat pipe interface.

FIG. 6 shows a heat pipe interface assembly consisting of a first plate assembly 72 and a second plate assembly 74 constructed as individual heat pipes with integral cavities 76 for accepting a first heat pipe 78 and a second heat pipe 80. In this configuration, first plate assembly 72 and second plate assembly 74 pivot about axis 82. A layer of heat conductive grease (such as Bray Oil Company Perfluorinated Ether Base Grease) could be used between the first plate assembly 72 and the second plate assembly.

FIG. 7 shows yet another possible variation of the basic principle of the present invention. In this configuration, the interface assembly 90 consists of a first block assembly 92 and a second block assembly 94 which then assembled adjacent to one another form a first cavity 96 and a second cavity 98. First cavity 96 would be substantially spherically shaped with a shaped entrance portion as shown in F IG. 7. The first cavity 96 would receive and contain the spherical end of a first heat pipe 100 which could move throughout the limits established by the size and shape of the entrance portion. Second cavity 98 would receive and contain one end of a second heat pipe 102. As with the pivoting interface of FIG. 6, a layer of heat conductive grease should be used between the moving parts.

Having thus described my invention, 1 claim:

1. Apparatus for interconnecting two or more heat pipes, being a composite structure comprising a plurality of plates held together by securing means wherein;

a. one of said plates is a heat pipe,

b. each of said plates is disposed with one side adjacent to the side of another of said plates,

0. said composite structure has a first cavity to hold the condenser portion of a first heat pipe to be interconnected with a second heat pipe, and

(1. said composite structure has a second cavity to hold the evaporator portion of the second heat pipe.

2. Apparatus for interconnecting two or more heat pipes as claimed in claim 1 wherein said securing means allows the portion of said composite structure containing said first cavity to pivot about a common axis in relation to that portion of said composite structure containing said second cavity.

3. Apparatus for interconnecting two or more heat pipes as claimed in claim 1 wherein said cavities are so shaped as to conform to the heat pipes contained therein in a manner which will maintain maximum thermal conductivity between the heat pipes and the portions of said composite structure forming the walls of said cavities.

4. Apparatus for interconnecting two or more heat pipes as claimed in claim 1 wherein one of said cavities is so shaped as to allow movement of the heat pipe contained therein while preventing removal of the heat pipe from said cavity and maintaining thermal conductivity with the heat pipe.

5. Apparatus for interconnecting two or more heat pipes as claimed in claim 4 wherein said cavity shaped as to allow movement of the heat pipe contained therein is spherically shaped.

6. Apparatus for interconnecting two or more heat pipes comprising two slab heat pipes and securing means wherein:

a. each of said two slab heat pipes is so shaped as to define a portion of a first cavity to contain the evaporator portion of a first heat pipe to be interconnected;

b. each of said two slab heat pipes is so shaped as to define a portion of a second cavity to contain the condenser portion of a second heat pipe to be interconnected,

c. said two heat pipes are disposed adjacent to each other such that said first cavity and said second cavity are fully defined, said two heat pipes being held in said position by said securing means. 

1. Apparatus for interconnecting two or more heat pipes, being a composite structure comprising a plurality of plates held together by securing means wherein; a. one of said plates is a heat pipe, b. each of said plates is disposed with one side adjacent to the side of another of said plates, c. said composite structure has a first cavity to hold the condenser portion of a first heat pipe to be interconnected with a second heat pipe, and d. said composite structure has a second cavity to hold the evaporator portion of the second heat pipe.
 2. Apparatus for interconnecting two or more heat pipes as claimed in claim 1 wherein said securing means allows the portion of said composite structure containing said first cavity to pivot about a common axis in relation to that portion of said composite structure containing said second cavity.
 3. Apparatus for interconnecting two or more heat pipes as claimed in claim 1 wherein said cavities are so shaped as to conform to the heat pipes contained therein in a manner which will maintain maximum thermal conductivity between the heat pipes and the portions of said composite structure forming the walls of said cavities.
 4. Apparatus for interconnecting two or more heat pipes as claimed in claim 1 wherein one of said cavities is so shaped as to allow movement of the heat pipe contained therein while preventing removal of the heat pipe from said cavity and maintaining thermal conductivity with the heat pipe.
 5. Apparatus for interconnecting two or more heat pipes as claimed in claim 4 wherein said cavity shaped as to allow movement of the heat pipe contained therein is spherically shaped.
 6. Apparatus for interconnecting two or more heat pipes comprising two slab heat pipes and securing means wherein: a. each of said two slab heat pipes is so shaped as to define a portion of a first cavity to contain the evaporator portion of a first heat pipe to be interconnected; b. each of said two slab heat pipes is so shaped as to define a portion of a second cavity to contain the condenser portion of a second heat pipe to be interconnected, c. said two heat pipes are disposed adjacent to each other such that said first cavity and said second cavity are fully defined, said two heat pipes being held in said position by said securing means. 